001/* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2013, by Object Refinery Limited and Contributors.
006 *
007 * Project Info:  http://www.jfree.org/jfreechart/index.html
008 *
009 * This library is free software; you can redistribute it and/or modify it
010 * under the terms of the GNU Lesser General Public License as published by
011 * the Free Software Foundation; either version 2.1 of the License, or
012 * (at your option) any later version.
013 *
014 * This library is distributed in the hope that it will be useful, but
015 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
016 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
017 * License for more details.
018 *
019 * You should have received a copy of the GNU Lesser General Public
020 * License along with this library; if not, write to the Free Software
021 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
022 * USA.
023 *
024 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. 
025 * Other names may be trademarks of their respective owners.]
026 *
027 * ---------------
028 * EmptyBlock.java
029 * ---------------
030 * (C) Copyright 2004-2008, by Object Refinery Limited.
031 *
032 * Original Author:  David Gilbert (for Object Refinery Limited);
033 * Contributor(s):   -;
034 *
035 * Changes:
036 * --------
037 * 22-Oct-2004 : Version 1 (DG);
038 * 04-Feb-2005 : Now cloneable and serializable (DG);
039 * 20-Apr-2005 : Added new draw() method (DG);
040 * 08-Apr-2008 : Added support for margin and border (DG);
041 * 08-May-2008 : Updated arrange() method to recognise
042 *               incoming constraint (DG);
043 *
044 */
045
046package org.jfree.chart.block;
047
048import java.awt.Graphics2D;
049import java.awt.geom.Rectangle2D;
050import java.io.Serializable;
051
052import org.jfree.ui.Size2D;
053import org.jfree.util.PublicCloneable;
054
055/**
056 * An empty block with a fixed size.
057 */
058public class EmptyBlock extends AbstractBlock
059        implements Block, Cloneable, PublicCloneable, Serializable {
060
061    /** For serialization. */
062    private static final long serialVersionUID = -4083197869412648579L;
063
064    /**
065     * Creates a new block with the specified width and height.
066     *
067     * @param width  the width.
068     * @param height  the height.
069     */
070    public EmptyBlock(double width, double height) {
071        setWidth(width);
072        setHeight(height);
073    }
074
075    /**
076     * Arranges the contents of the block, within the given constraints, and
077     * returns the block size.
078     *
079     * @param g2  the graphics device.
080     * @param constraint  the constraint (<code>null</code> not permitted).
081     *
082     * @return The block size (in Java2D units, never <code>null</code>).
083     */
084    @Override
085    public Size2D arrange(Graphics2D g2, RectangleConstraint constraint) {
086        Size2D base = new Size2D(calculateTotalWidth(getWidth()),
087                calculateTotalHeight(getHeight()));
088        return constraint.calculateConstrainedSize(base);
089    }
090
091    /**
092     * Draws the block.  Since the block is empty, there is nothing to draw
093     * except the optional border.
094     *
095     * @param g2  the graphics device.
096     * @param area  the area.
097     */
098    @Override
099    public void draw(Graphics2D g2, Rectangle2D area) {
100        draw(g2, area, null);
101    }
102
103    /**
104     * Draws the block within the specified area.  Since the block is empty,
105     * there is nothing to draw except the optional border.
106     *
107     * @param g2  the graphics device.
108     * @param area  the area.
109     * @param params  ignored (<code>null</code> permitted).
110     *
111     * @return Always <code>null</code>.
112     */
113    @Override
114    public Object draw(Graphics2D g2, Rectangle2D area, Object params) {
115        area = trimMargin(area);
116        drawBorder(g2, area);
117        return null;
118    }
119
120    /**
121     * Returns a clone of the block.
122     *
123     * @return A clone.
124     *
125     * @throws CloneNotSupportedException if there is a problem cloning.
126     */
127    @Override
128    public Object clone() throws CloneNotSupportedException {
129        return super.clone();
130    }
131
132}